URIteacherknowledge - Mechanisms of Evolution Fitness & Natural Selection

Lesson Title: Lesson 6 Mechanisms of Evolution Fitness & Natural Selection

State Standards:

Natural selection provides the following mechanism for evolution: Some variation in heritable characteristics exists within every species; some of these characteristics give individuals an advantage over others in surviving and reproducing; and the advantaged offspring, in turn, are more likely than others to survive and reproduce. As a result, the proportion of individuals that have advantageous characteristics will increase. 5F/H3*

Context of Lesson:

In the previous lesson, we completed an activity that demonstrates the advantage of camouflage as a strategy for survival and reproduction; this lesson brings variations in predator capture strategies to the fore and will further the students' knowledge of the concept of fitness as it relates to survival and reproductive advantage for the predators in varying environments
The activity is designed as an inquiry exercise and the materials have been supplied by Carolina Biological Supply Inc.
The kit provided is one of the first in a new series of inquiry based lab kits developed by the manufacturer.
The lesson will encompass one 66 min period

Materials:

Carolina Biological Supply: Simulating Darwin Scientific Inquiry Lab Kit which includes the following:
- colored pom poms
- spoons
- forks
- sticks
- plastic forceps
- plastic cups
- sand
- colored background materil
- water tray
- datasheets

Objectives:

Students will demonstrate an understanding of the factors contributing to fitness by engaging in an exercise that simulates the dynamic between capture techniques of a predator and the survival rate of a prey given varying environmental scenarios.

Instruction:
Opening:

Class time	Activity	Description
5 min	Welcoming	I will stand at the door of the Biology Lab and greet students as they enter the classroom We will address their "15 minutes of fun" and clear up any questions that may have arisen from the previous day's activity
10 min	Setup	I will divide the class into 7 groups of four. The groups will be chosen with the intent of ensuring that the better students are present in each of the seven groups and that any students who should not be together are separated I will introduce the engagement material provided (see S-1 below) in order to activate knowledge as a prelude to the activity The students will be free to ask any questions that arise at this time *

Engagement:

Class time	Activity	Description
5 min	Ready-up	Prior to the activity, 7 different stations will be setup within the lab. Each station will have one of the three different envronments as specified in the manual (see below) The students will rotate through three of the stations, ensuring that they experience each of the different environmental scenarios at least once. (more if time allows) The students will read the instructions & I will reinforce through verbal direction
30 min	Fun with spoons & sticks	Students will check to be sure that each station is setup according to the instructions and be poised at the ready. There will be a 30 second* time limit at each predation run & I will keep time (or assign one student to do so) There will be at least two predation events and two succeeding reproduction periods for each group at each station (as per the instructions, see below)
		*The time limit at each station may change in order to better fit the exercise.
		The students will collect population data in between each event and record the results on their data sheets When the students have completed the simulations for two generations, they will reset their stations with the appropriate number of pom poms in each environment and then they will be asked to rotate their group to a different environment & repeat the exercise at each new station The exercise will continue until each group has experienced each of the environments at least once and collected data from each trial. As a group the students will analyze their data by calculating percentages of succeeding populations and creating a graphic representations of their results (see S-4, below) As the students are working on their graphs, I will remove the inquiry materials from their respective stations and be available to answer any questions that may arise.

Closure:

Class time	Activity	Description
15 min	Group Analysis	Students will be given a bank of questions that ask them to analyze their data and explain why each population changed as they did.


		Students will spend the rest of the period working on their analysis, while I circulate through the room to clear up any problems that may present themselves. If the analysis is incomplete, then the students will finish their analysis as a homework assignment Tomorrow we will begin class by discussing the results and offer some reasonings as to why the populations change as they did

Assessment:

Students will be assessed based on the evidence of understanding written in the data and analysis sheets
The content & concepts will also be addressed on the end of unit exam